For example, in a manufacturing process of a semiconductor device, photolithography processing is performed in which a resist coating treatment of applying a resist solution onto, for example, a semiconductor wafer (hereinafter, referred to as a “wafer”) to form a resist film, exposure processing of exposing the resist film to a predetermined pattern, a developing treatment of developing the exposed resist film and so on are performed in sequence to form a predetermined resist pattern on the wafer. Then, using the resist pattern as a mask, an etching treatment is performed on a film to be treated on the wafer and a removal treatment of the resist film is then performed, to form a predetermined pattern in the film to be treated.
Incidentally, for higher integration of the semiconductor device, miniaturization of the above-described pattern of the film to be treated is required in recent years. Therefore, the resist pattern is increasingly miniaturized and, for example, the wavelength of light for the exposure processing in the photolithography processing is increasingly shortened. However, there are technical and cost limits in shortening the wavelength of an exposure light source, and it is now difficult to form a fine resist pattern on the order of, for example, several nanometers only by the method of increasingly shortening the wavelength of light.
Hence, there is a proposed wafer treatment method using a block copolymer composed of two kinds of hydrophilic and hydrophobic block chains (polymers) (Patent Document 1). In this method, first, a guide is formed on the wafer, for example, by a resist pattern. Then, a block copolymer is applied onto the wafer, and a heat treatment is performed on the block copolymer to phase-separate the block copolymer into a hydrophilic polymer and a hydrophobic polymer. Thereafter, irradiation with an ultraviolet ray is performed on the wafer to modify the polymer. By supplying an organic solvent onto the wafer, the hydrophilic polymer is selectively removed. This forms a fine pattern of the hydrophobic polymer on the wafer.